Chapter 3.1 Chemistry of Life

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Life Science Chapter 3: Cell Processes 1. Chemistry of Life 2. Moving Cellular Materials 3. Energy for Life http://www.connecticutvalleybiological.com/cell processes vhs p 14026.html Chapter 3.

1 Life Science Chapter 3: Cell Processes 1. Chemistry of Life 2. Moving Cellular Materials 3. Energy for Life processes vhs p html Chapter 3.1 Chemistry of Life Learning Objectives: 1. List the differences among atoms, elements, molecules, and compounds. 2. Explain the relationship between chemistry and life science. 3. Discuss how organic compounds are different from inorganic compounds. Vocabulary: mixture, organic compound, enzyme, inorganic compound Matter is anything that has mass and takes up space. Examples? Energy is anything that brings about change. can hold matter together or break it apart. 1

jpg Atoms Electrons Around the nucleus is a cloud of electrons (have a charge). Constantly moving VERY small mass compared to protons and neutrons!

2 Atoms All matter (whether solid, liquid, or gas) is made of atoms. Center of atom is called the nucleus. The nucleus consists of: protons (have a + charge) neutrons (have no charge) Atoms Electrons Around the nucleus is a cloud of electrons (have a charge). Constantly moving VERY small mass compared to protons and neutrons! The mass of 1,837 electrons = the mass of 1 proton Involved in CHEMICAL REACTIONS pointer/how laser works freaklasers 1.jpg Matter vs. Energy Matter Energy Definition Examples atoms, electrons, protons, and neutrons;,,,, sunlight, electricity, heat, chemical energy 2

can t be broken down into simpler form by chemical reactions. are known by their own one or two letter symbol.

3 Parts of an Atom Protons Electrical Charge? Location in Atom? Relative Mass? Neutrons Electrons Elements are made up of only one kind of atom. can t be broken down into simpler form by chemical reactions. are known by their own one or two letter symbol. make up everything in the Universe. content/uploads/2009/07/periodic tableelements au ring.jpg table.gif table 2.jpg 3

4 How many of these elements can you identify? O C H N Ca P K S Na Cl Mg Elements that make up the human body 99% of living matter is made up of six (6) elements. That makes these elements pretty important! S P O N C H 4

Compounds and Molecules Compounds composed of molecules Molecules of compounds have atoms of 2 or more elements bonded together. Example: water http://kentsimmons.uwinnipeg.ca/cm1504/introchemistry.

These elements are in exact proportions. Example: Water is always made up of hydrogen atom(s) and oxygen atom(s), bonded together in exactly the same way, to form a water molecule.

5 Compounds and Molecules Compounds composed of molecules Molecules of compounds have atoms of 2 or more elements bonded together. Example: water Compounds and Molecules Compounds composed of molecules Molecules of compounds have atoms of 2 or more elements bonded together. These elements are in exact proportions. Example: Water is always made up of hydrogen atom(s) and oxygen atom(s), bonded together in exactly the same way, to form a water molecule. Compounds and Molecules Molecular Compounds form when different atoms share their outermost electrons. Hydrogen atoms have 1 electron. How many electrons does an oxygen atom have? (see pg. 66) On Earth, Oxygen and hydrogen normally exist as gases. But as a compound (water), they can be liquid, solid, or gas. **When a compound is formed, changes occur and a new substance forms. 5

Compounds Found in All Living Things There are four groups: 1.

6 Organic and Inorganic Compounds What s the difference? Characteristic ORGANIC COMPOUNDS INORGANIC COMPOUNDS Contain elements: Associated with: Relative # of atoms: Examples Organic Compounds Found in All Living Things There are four groups: Carbohydrates Elements: carbon, hydrogen, oxygen Examples: sugars, starch, cellulose What function do they have? 1. Supply energy for cell processes 2. Form plant structures 3. Short term energy storage 6

2. Lipids Elements: carbon, hydrogen, oxygen,

phospholipids, cholesterol What function do they

Store large amounts of energy long term 2.

gov.hk/english/safefood/nutrient/1.html 3.

nitrogen, sulfur Examples: enzymes, skin, hair

Build cell structures http://www.fehd.gov.

Nucleic Acids Elements: carbon, hydrogen, oxygen,

7 2. Lipids Elements: carbon, hydrogen, oxygen, phosphorus Examples: fats, oils, waxes, phospholipids, cholesterol What function do they have? 1. Store large amounts of energy long term 2. Form major part of cell membranes 3. Proteins Elements: carbon, hydrogen, oxygen, nitrogen, sulfur Examples: enzymes, skin, hair What function do they have? 1. Regulate cell processes 2. Build cell structures 4. Nucleic Acids Elements: carbon, hydrogen, oxygen, nitrogen, phosphorus Examples: DNA & RNA What function do they have? 1. Carry hereditary information 2. Used to make proteins 7

Inorganic Compounds Made from elements other than carbon. that living things need.

contain the elements nitrogen, phosphorus, and sulfur.

Hydrochloric acid Sodium bicarbonate Salts containing S, Cl, and K Use in Body Blood;

8 Inorganic Compounds Made from elements other than carbon. that living things need. Example: Plants take up inorganic compounds from soil. These I.C. contain the elements nitrogen, phosphorus, and sulfur. Some Inorganic Compounds Important in Humans: Compound Water Calcium phosphate Hydrochloric acid Sodium bicarbonate Salts containing S, Cl, and K Use in Body Blood; chemical reactions Bone strength Breaks down foods in stomach Digestion Nerve messages 8

Ch. 3.3 Energy for Life (p. 81) Why It s Important: Because of photosynthesis and respiration, you use the Sun s energy. What You ll Learn: 1. List the differences between producers and consumers. 2.

Vocabulary: metabolism, respiration, photosynthesis, fermentation How do we get energy from the food we eat? Chemical reactions! Food contains chemical energy.

9 Ch. 3.3 Energy for Life (p. 81) Why It s Important: Because of photosynthesis and respiration, you use the Sun s energy. What You ll Learn: 1. List the differences between producers and consumers. 2. Explain how the processes of photosynthesis and respiration store and release energy. 3. Describe how cells get energy from glucose through fermentation. Vocabulary: metabolism, respiration, photosynthesis, fermentation How do we get energy from the food we eat? Chemical reactions! Food contains chemical energy. Using chemical reactions, cells change this chemical energy into forms needed to perform all of the activities necessary for life. All of your activities involve chemical reactions. Metabolism: The total of all chemical reactions in an organism. The chemical reactions in your cells need enzymes. Enzymes are like can openers. You need a can opener to open the can. The can changes, but the can opener doesn t it can be used over and over again. Enzymes can break molecules apart (like a can opener), but enzymes also can cause molecules to join (unlike a can opener). 9

10 BUT just any old enzyme won t do! There has to be a perfect fit between a particular molecule and a particular enzyme. +Baking+Enzyme BUT just any old enzyme won t do! There has to be a perfect fit between a particular molecule and a particular enzyme. +Baking+Enzyme Photosynthesis Living things are divided into two groups based on how they obtain FOOD:

11 Greek and Latin Word Roots Are Fun (and Useful!) Photo means. Synthesis means. Photosynthetic Protists Euglena Algae Photosynthetic Bacteria Stromatolites formed by cyanobacteria Ancient oxygen producers 3.5 billion years old! Cyanobacteria hamburg.de/bonline/library/webb/bot311/cyanobacteria/cyanobacteria.htm 11

Photosynthesis During photosynthesis, producers use light energy to make

is a green pigment that captures sunlight energy.

In plants, this pigment is found in organelles called.

soil) Captured by chlorophyll, the Sun s energy drives chemical reactions

12 Photosynthesis During photosynthesis, producers use light energy to make sugars, which can be used as food. is a green pigment that captures sunlight energy. It s what makes green plants green! In plants, this pigment is found in organelles called. PHOTOSYNTHESIS IN PLANTS Raw Materials: Carbon Dioxide (from air) Water (from soil) Captured by chlorophyll, the Sun s energy drives chemical reactions Products: Sugar Oxygen (Don t forget the enzymes!) CO 2 + H 2 O + light energy Chlorophyll C 6 H 12 O 6 + O What kind of organic compound is SUGAR? 12

Storing Carbohydrates Plants make more sugar than they need to survive. Excess sugar is changed and stored as starches or used to make other carbohydrates.

com/3)+the+cell http://www.uic.edu/classes/bios/bios100/lectures/ps01.

13 Storing Carbohydrates Plants make more sugar than they need to survive. Excess sugar is changed and stored as starches or used to make other carbohydrates. Plants use these carbohydrates as food for growth, maintenance, and reproduction. What about food we eat? How is it connected to photosynthesis? Respiration During respiration, chemical reactions occur that break down food molecules into simpler substances and release their stored energy. Respiration occurs in the cells of all living things. Most cells need oxygen to break down food. Enzymes are also needed for the chemical reactions to occur. 13

Respiration: Breaking Down Carbohydrates Out of all the types of food, carbohydrates are most easily broken down by cells. Respiration of carbohydrates begins in cytoplasm of cell.

14 Respiration: Breaking Down Carbohydrates Out of all the types of food, carbohydrates are most easily broken down by cells. Respiration of carbohydrates begins in cytoplasm of cell. Carbohydrates broken down into glucose molecules Then each glucose molecule is broken down into two simpler molecules, releasing ENERGY. Respiration, cont d So far Carbohydrates glucose molecules two simpler molecules In mitochondria (most organisms), two simpler molecules broken down again using oxygen. Produces much more energy than breakdown of glucose molecules did Produces carbon dioxide and water as wastes (humans exhale these) Fermentation Not enough oxygen for respiration? Fermentation is used to release to release some of the energy stored in glucose molecules when cells don t have enough oxygen. Example: when you run so hard that you have to breathe rapidly 14

Process of Fermentation Starts in cytoplasm (like respiration) and ends in cytoplasm (unlike respiration, which finishes in mitochondria) Like

15 Process of Fermentation Starts in cytoplasm (like respiration) and ends in cytoplasm (unlike respiration, which finishes in mitochondria) Like respiration, starts with breakdown of glucose molecules into simpler molecules to release some energy These simpler molecules are broken down again to release more energy, producing wastes. Wastes may include lactic acid, alcohol, and carbon dioxide Lactic acid makes muscles feel stiff Fermentation in Action The Big Picture How are the processes of photosynthesis, respiration, and fermentation related? 15

Chapter: Cell Processes

Table of Contents Chapter: Cell Processes Section 1: Chemistry of Life Section 2: Moving Cellular Materials Section 3: Energy for Life 1 Chemistry of Life The Nature of Matter Matter is anything that has